Electricity connects our everyday lives. But other than flicking switches on and off, how does electricity work?
Many of us are familiar with electricity-related terms like electrons, ohms, and Benjamin Franklin, but there’s a lot more to the story. Let’s look at how electricity is made and get a clear understanding of how it works.
How Does Electricity Work?
At its most fundamental level, electricity is the movement of electrons between atoms. A long line of electrons bangs into each other, creating an electrical flow. However, we need to move to the atomic level to get a better understanding of how electricity really works.
All About Atoms
Atoms are the minuscule building blocks of the universe — everything within the universe is made of atoms — and each one measures a tenth of a millionth of a millimeter across (0.0000001 mm). To give you an idea of how tiny that is, a pinhead is estimated to be made up of five million atoms.
Within each atom is a nucleus, which is made up of protons and neutrons orbited by electrons. These electrons are held in place by an electrical force and housed in shells, called inner and outer shells. There are thought to be the same number of protons and electrons in the universe.
Protons carry a positive charge (+), and electrons a negative charge (-), signs we are used to seeing on batteries. Protons and electrons have an electrical charge, and that charge is the same for both. They are attracted to each other — as Paula Abdul famously sang, opposites attract. It was Benjamin Franklin who discovered the electric charge and named the positive and negative charges.
Electrons move at a constant distance from the nucleus, held in their shell’s orbit by an electrical force. In this state, an atom is in balance. Inner shell electrons are strongly attracted to the protons, but outer shell electrons can be moved. If you apply sufficient force to an outer shell electron, it can be pushed towards another atom. These shifting electrons are what create electricity.
We harness this movement of charged particles — the electric charge — via conductors like copper wire, which send electrical current from a power source to something we wish to power. The electrons don’t travel along the wire; they bang into each other, passing on the electrical charge, and the electricity flows when we make a complete electrical circuit. This process is what gives us the electrical current to power our lights, washing machines, and more.
Static electricity takes us back to Benjamin Franklin and his famous experiment of 1752. He flew a kite in a thunderstorm to catch electrical energy — you must not do this under any circumstance — and a lightning bolt hit the kite and traveled down to the Earth. Fortunately, Franklin was well insulated, and he deduced that the sky’s static electricity became current during his experiment.
Static electricity is all around us. When you rub a balloon on a jumper, it sticks. The movement pushes free electrons from your now positively-charged jumper to the now negatively-charged balloon. Opposites attract, and so the two materials adhere together.
Two titans in the history of electricity are Thomas Edison and Nikola Tesla. They dueled in what became known as the War of the Currents. Edison developed direct current, or DC, which runs in one direction and is hard to convert to higher or lower voltages.
Nikola Tesla proposed alternating current (AC) as the remedy. Alternating current changes direction rapidly. In the United States, this happens 60 times per second. A transformer helps change the voltage easily in alternative current systems.
Alternating current prevailed in the 19th century, but DC has made a comeback of late. Computers and electric cars use DC and modern technology enables voltage variations. Direct current is constant, so electricity can be transported long distances along high voltage power lines with less power loss.
How Is Electricity Made and What Is It Made Of?
Now that we know how electricity works, we can look at how electricity is made.
When we move electrons we get electrical energy. Electricity itself is the name we give to the type of energy that comes from this electrical energy.
In general, electricity is produced in power stations and, more recently, in renewable forms like wind turbines, solar panels, and hydropower. Regardless of the sources of energy, the same method is used to make electricity using electric generators:
Magnets + copper wire + spinning motion = electric current
Power stations house enormous steam turbines, which turn large magnets very quickly within copper wire coils, called generators. Be it nuclear energy, hydroelectricity, or solar energy, turbine generators spin the magnets.
We use copper wire because of its ability to conduct electricity well. Copper wiring uses insulators like rubber to house the wire in cables so we don’t get electric shocks.
Back to the power station. The rapidly rotating magnets are pushing the electrons around, creating a magnetic field and a flow of electrons that move down the copper wire. The current moves to the power grid transmission lines and electrical substations then to our homes and businesses.
This flow of electrons is what makes up the electricity.
How Is Energy Measured? In What Units?
We measure electricity and electrical units using several systems that are all interlinked. A useful analogy is to think of an electrical circuit as a closed circuit of water pipes.
The first measurement to consider is the ampere, or amp (A). This unit measures an electric current under the International System of Units (SI). The ampere is the constant current or number of electrons that flow through a circuit — or our water flowing through a pipe.
An ohm (Ω)is how we measure electrical resistance. Copper wire is a good conductor and has a meager resistance, so it permits an easy flow of electrons and has a low ohm reading (0.0000017 ohms). Think of ohms as the diameter of the water pipes in your circuit.
A volt (V)is the measurement of the force that pushes electrons through an electric circuit, also known as the electric potential difference. Voltage is the potential for energy to move. Using the water pipe example again, the higher the pressure, the higher the voltage.
All of these units are interconnected. One amp equals the amount of current produced by a force of one volt acting through the resistance of one ohm.
A watt (W) is a measurement of power, the rate at which work is being done, and named after Scottish inventor James Watt. We’re familiar with seeing these on light bulbs, which were invented by Thomas Edison. A brighter light bulb requires more power, hence its higher wattage. A one-watt light bulb converts one joule of electrical energy every second.
Finally, we have coulombs, which is the SI measurement of charge. The Khan Academy defines coulombs as the amount of charge flowing when the current is 1 ampere.
1 ampere = 1 coulomb/second
1 coulomb = 1 ampere⋅second
Why Is Electricity Important?
Electricity is an essential form of energy throughout our lives, and we have an ever-increasing dependence on electric power. Heating, lighting, and appliances run on electricity, and soon electric cars with electric motors will be a much more common sight worldwide.
As long as we can turn magnets around copper wire quickly enough in generators, we can create electricity. Wind turbines, hydroelectric power, steam-driven geothermal power plants, and other renewable energy sources mean that if we make electricity our primary source of power, we can create clean power for millennia.
Where Does My Electricity Come From?
You can check where your electricity comes from by asking your energy supplier. In the United States, the fossil fuels of coal, natural gas, and petroleum are the three major electricity generation sources. Nuclear power plants, wind energy, biomass, and hydroelectric stations also produce electricity.
Why Is Electricity Not an Energy Source?
Electricity is a way of transporting energy from one place to another; it is not an energy source in itself and is considered a secondary energy source.
Fossil fuels, nuclear power, or renewable energy sources like wind power or solar power drive the turbines and generators that create electricity, an energy carrier. Once electricity has been generated and transported, its energy is converted into other forms of energy — for example, mechanical energy such as the electric motor in an electric car.
Every household has a wide range of electrical appliances with varying wattages and voltages. All of them are full of electrical components, from resistors to capacitors to transistors. But how much electricity do they use, and what is the cost to you as a consumer?
You can always lower your bills by switching your current electricity supplier. They can also help you choose which fuel source you prefer. Fossil fuel-powered stations produce carbon dioxide, spouting harmful emissions in the atmosphere.
The best way to work out how much electricity an appliance is using is to look at how much power they use in watts. For United States residents, this appliance energy calculator can give an estimate of how much each appliance costs to run.
How Much Electricity Does a TV Use?
The amount of electricity your TV uses usually depends on the size of its screen. Here are some approximate values:
- 22″ LED TV: 17 watts
- 42″ LED TV: 58 watts
- 65″ LED TV: 120 watts
It costs around three cents a day to keep a 42″ LED TV on for four hours, based on 12 cents per kilowatt-hour pricing.
How Much Electricity Does a Computer Use?
- Chromebook: 45 watts
- Amazon Echo Dot: 2 watts
- Playstation 4: 300 watts
It costs around 14 cents a day to keep a Playstation 4 on for four hours, based on twelve cents per kilowatt-hour pricing.
How Much Electricity Does a Light Bulb Use?
The energy use of a lightbulb is simpler to show: look for watts on the packaging. It costs around five cents a day to keep a 100W light bulb on for four hours, based on 12 cents per kilowatt-hour pricing.
How Much Electricity Does an Oven Use?
Ovens come in all shapes and sizes, and dishes demand different cooking temperatures and duration. Most cooking is performed between 300-425 degrees Fahrenheit (150-220 Celsius), and most ovens use between 1,000-5,000 watts, with the average modern oven using around 2,400W.
It costs around 30 cents to keep a 2,500W oven on for an hour, based on 12 cents per kilowatt-hour pricing.
How Much Electricity Does the AC Use?
Air conditioning units come in all manner of configurations. Total use depends on outside temperature, desired inside temperature, number of rooms, insulation, AC model, and much more. An apartment in New York City won’t have the same air conditioning needs as a house in Los Angeles.
An average central AC unit running for nine hours a day in summer months could use 3,000-5,000 watts of power. At 4,000W, that means an AC unit costs 48 cents to run every hour, based on 12 cents per kilowatt-hour pricing.
How Much Electricity Does a Dryer Use?
A clothes dryer has a wide range of wattage usage, from 1,800-5,000 watts. The average machine uses around 3,000 watts. Using a 4,000W unit costs 36 cents to run for an hour, based on 12 cents per kilowatt-hour pricing.
Do Dimmers Use Less Electricity?
The short answer is yes. Modern dimmers do use less electricity. Older dimmers would add resistance to the circuit, and instead of creating light, the electricity would generate more heat.
Modern dimmers use a TRIAC switch to cut the electricity supply off and on hundreds of times every second. The amount of power reaching the light bulb is less, making it dimmer and using less electricity.
How Much Electricity Do I Use?
You’ll need to study a few of your previous electricity bills to work this out. Electricity usage varies with seasons, weather, and many other factors.
Check the billing period and also the energy used on your electricity bill. There should also be a section called “Usage.” This should be given in kilowatt-hours used (kWh) and show how much each kilowatt-hour costs.
If you want to work out how much electricity you are using on each appliance, take its wattage and multiply it by how many hours you use it each day.
What’s the Average Household Electricity Usage?
According to the U.S. Energy Information Administration, the average annual electricity consumption for a U.S. residential utility customer in 2019 was 10,649 kilowatt-hours (kWh), an average of around 877 kWh per month.
Louisiana was the highest with 14,787 kWh annual electricity consumption per residential customer, and Hawaii the lowest at 6,296 kWh.
By contrast, in 2018, the average U.K. annual electricity consumption per residential customer ranged between 3,231—4,153 kWh.
Electricity Works for All of Us
Electricity is a secondary energy source created at an atomic level thanks to the attraction of protons and electrons. It’s generated when we move electrons around. When we move that energy down conductive wires, the electricity travels into our homes and businesses. We convert electrical power into useful mechanical energy to power machines to enhance our daily lives.
Brought to you by amigoenergy
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